Rapid screening of toxic glycoalkaloids and micronutrients in edible nightshades ( Solanum spp.)

Abstract

African indigenous vegetables (AIVs) because of their nutrient density have the unique potential to reduce micronutrient deficiencies in sub-Saharan Africa, yet some may also contain anti-nutritive compounds. Vegetable nightshades from Solanum americanum, Solanum nigrum, Solanum scabrum and Solanum villosum are among the major AIVs used as a leafy vegetables and consumed regularly in many countries in sub-Sahara Africa. These under-recognized food crops have not been subjected to extensive studies for their nutritional and antinutritive factors. In this study, 15 entries of the vegetable nightshades were field-grown and the leaves which are the consumed product of commerce chemically profiled by LC/ESI-MS. Twenty-three flavones, eight saponins, and two glycoalkaloids along with a phenolic acid of chlorogenic acid were identified by MS and UV data. Anti-nutrient glycoalkaloids were quantified as total aglycones after acidic hydrolysis using MS detection and found to be within safe-consumption thresholds by comparison with the glycoalkaloid level in the globally consumed Solanum member eggplants. Edible nightshades were also found to be sources of β-carotene, vitamin E and total polyphenols and exhibited high antioxidant activity. Results of this study support that consumption of vegetable nightshades are safe from the presence of glycoalkaloids and thus, can contribute to the reduction of micronutrient deficiency in sub-Sahara Africa.

Identification of Polyphenols, Glycoalkaloids, and Saponins in Solanum scabrum Berries Using HPLC‐UV/Vis‐MS

“…Despite the rarity of formation of radicals in ESI, the formation of radical ions could be rationalized by the extended conjugation in the molecules, and similar phenomena could also be observed in other methylated flavonoids (Wu, Wang, & Simon, ). It is of interest to note that isomer rhamnetin was found in the leaves of S. scabrum with methyl substitution occurring on the A ring (Yuan et al., ).…”

Host plant defenses of black (Solanum nigrum L.) and red nightshade (Solanum villosum Mill.) against specialist Solanaceae herbivore Leptinotarsa decemlineata (Say)

“…For this purpose, the plants extracts were screened for their bioactive components and α‐solasonine is was found to be one of their leaf constituents. Many reports in the literature showed the richness of SGA in these plants (Rajalashmi & Jayachitra, ; Yuan et al, ) and correlate their presence with antioxidant activity, antibacterial activity, and antitumor effects (Rajalashmi & Jayachitra, ). The presence of α‐solasonine in leaf extract of S. nigrum and S. villosum was not connected to the insecticidal activity against CPB, as it did not exhibit potent GST inhibitory activity.…”

African Nightshade (Solanum scabrum Mill.): Impact of Cultivation and Plant Processing on Its Health Promoting Potential as Determined in a Human Liver Cell Model

“…With increasing demand for this crop in markets, farmers in peri-urban areas have consequently increased its production. The leaves of Solanum species are more consumed than the fruits since these can contain high amounts of anti-nutrients such as solanaceous glycoalkaloids like solasodine [ 4 ]. For the leaves, this is normally less [ 4 ] but they are cooked or fermented with milk to reduce these bitter tasting compounds [ 4 ].…”

“…The leaves of Solanum species are more consumed than the fruits since these can contain high amounts of anti-nutrients such as solanaceous glycoalkaloids like solasodine [ 4 ]. For the leaves, this is normally less [ 4 ] but they are cooked or fermented with milk to reduce these bitter tasting compounds [ 4 ]. Glycoalkaloids have not been detected in S. scabrum but in S. nigrum and S. villosum [ 4 ].…”

“…For the leaves, this is normally less [ 4 ] but they are cooked or fermented with milk to reduce these bitter tasting compounds [ 4 ]. Glycoalkaloids have not been detected in S. scabrum but in S. nigrum and S. villosum [ 4 ]. Processing conditions including cooking or fermentation, have been reported to impact the phytochemical content of vegetables and fruits [ 5 , 6 , 7 , 8 , 9 ].…”